Electrical conductor



VH. A. DOUGLAS.

vELECTRICAL CONDUUTOR.

APPLICATION FILED FEB. 4, 1918.

Patented May 11, 1920.

Illa

HARRY A. DOUGLAS, 0F BRONSON, MICHIGAN.

ELECTRICAL CONDUCTOR.

Specicaton of Letters Patent.

Patented May 11, 1920.

Application led February 4, 1918. Serial No. 215,331.

To all fw from 'it may comme/n Be it known that I, HARRY A. DOUGLAS, citizen of the United States, residing at Bronson, in the county of Branch and State of Michigan, have invented a certain new and useful Improvement in Electrical Conductors, of which the following is a fully clear, concise, and exact description.

My invention relates to sowcalled electrical conductors and has for its object the provision of an improved terminal construction for current conducting wire.

In practising my invention I employ two elements, one in the form of a sleeve and the other in the form of a collar surrounding the sleeve, this collar having a wire engaging end wall, and wire passing through the bore of the sleeve and having an end portion returned upon the exterior of the sleeve to form a bight in the wire at one end of the sleeve, there being space between lateral portions of the collar and sleeveV for receiving said end portion of the wire, said bight being engaged by the aforesaid end wall of the collar to maintain the bight in the wire in firm-engagement with said sleeve and collar.

In the preferred embodiment of the invention the sleeve `is exteriorly threaded and the collar is in the form of a nut threaded upon the sleeve. The returned end of the wire is desirably received in an external recess upon the lateral portion of the sleeve. The construction which I have devised is of particular service where the conducting wire is subdivided into fine strands, commonly called tinsel. Where the wire is thus subdivided into strands the conductor is in the nature of a so-called electrical cord that is highly'flexible in order that the conductor may be freely manipulated and adapted to varying environments.

An electrical conductor having flexible strands and constructed in accordance with my inventionlis of use in including lamp receiving sockets in circuit, establishing circuit relation of the electrical connectors, and in wire plugs, though it will be obvious that the invention is not to be limited to these particular purposes. y

I will explain my invention more fully by reference to the accompanying drawing showing the preferred embodiment-thereof and in which Figure 1 is a view, partially in section and partially in elevation, illustrating a socket wired by the device of my invention; Fig. 2 is a longitudinal sectional view of an electrical conductor and terminal elements pertaining thereto constructed and assembled in accordance with the invention, this figure being a detail that illustrates the lateral plug at the left hand end of the structure shown in Fig. l; Fig. 3 is a sectional view on line 3-3 of Fig. 2; Fig. i illustrates a connector having a plug wired by the device of my invention; Fig. 5 yis a view on line 5 5 of Fig. fl; Fig. 6 is a longitudinal sectional view of the electrical conductor and terminal elements pertaining thereto that are employed in the structure of Fig. 4c; Fig. 7 illustrates a form of socket having a removable plug which is wired by my improved conductor; Fig. 8 is a view on line 8--8 of Fig. 7; and Fig. 9 is a longitudinal sectional view of the electrical conductorl and terminal elements pertaining thereto that are employed in the structure of Fig. 7 Y Like parts are indicated by similar characters of reference throughout the different figures.

Reference willfirst be made to the construction shown in Figs. 1, 2 and 3 which illustrate the adaptation of my invention to a lamp socket that includes a metallic shell l in one end of which is permanently secured a plug 2 of insulation. The other end of this shell is formed with bayonet lslots 3 adapted to receive the bayonet pins l upon the base of an incandescent lamp 5. The structure illustrated is a socalled single pole'structure vin which one terminal of the lamp filament 6 is connected with a metallic sheath 7 that surrounds parts of the lamp and has electrical engagement with the metallic shell 1 that is suitably connected with one terminal of a source of current. The other terminal of the filament 6 is in the nature of a button 8 which is engaged by the contact plunger 9 that is pressed forwardly by a coiledspring l0. This coiled spring presses another contactV plunger 1.1 rearwardly. These contact plungers project through the ends of ya metallic spring barrel l2 that serves to include the contact plungers in circuit. The plug 2 has a lateral opening which receives the electrical conductor of my invention. As illustrated, this conductor is also in the nature of a plug having a contacting element 13 connected with the other terminal of the aforesaid source of current and which is provided with a peripheral groove 111 to receive the hemispherical rear end of the contact plunger 11 to complete the circuit of the lamp ilament 6 when such circuit is elsewhere established. The contacting element 13 is in the nature of a nut or collar and this collar is preferably in the form of a metallic nut having a threaded bore and formed with a wire engaging end wall. 15 which preferably, though not necessarily, closes one end of the bore of the nut. lire 16, by means of which the contact element 13 is connected with the source of current, is preferably subdivided into a number of strands in order that it may be flexible to a high .degree to constitute a so-called conducting cord. This wire passes through a metallic sleeve 17 which is threaded upon its exterior so that the nut 13 may be screwed thereupon. The sleeve 17 has an enlargement or extension 171 to receive the serving or insulation 18 that covers the wire 16, this serving being desirably absent where the wire passes through the threaded sleeve or sleeve section. The wire 16 passes through the bore of the sleeve 17 and has an end portion 161 which is returned upon the exterior of the sleeve 17 to form a bight 161 in the wire 16 at the outer end of the sleeve 17. The space between lateral portions of the nut 13 and the sleeve 17 that receives the wire end 161 is desirably provided by forming an external recess 19 in the sleeve 17 that is of a size snugly to receive thewire end 161. The bight 162 in the wire 16 is engaged by the end wall 15 of the nut 13'to maintain this bi glit in firm engagement with the nut 13 and sleeve 17 The connector shown in Figs. L1 and 5 is a so-called single pole connector that receives a lamp which is similar to the lamp shown in Fig. 1, like parts of the two lamps being given similar characters of reference.

The shell 11 has bayonet slots 31 for receiving the bayonet pins 1 projecting from the base of the lamp. The plug 21 is received in the intermediate portion of the shell and supports two oppositely spring pressed plunger contacts 91, 111, the plunger contact 91 being engageable with the lamp base contact 8 while the plunger contact 111 is'engageable with the end of another form of metallic nut 131 instead of with a side of such a nut that is the case with the construction shown in Fig. 1. This nut 131 is assembled With the split halves of an insulating core 20 which has a bore extending therethrough that receives the conductor structure that includes the nut 131 in circuit connection. IVth the exception of the nut, this conductor structure (detailed in Fig.

6) is similar to the structure shownv in Fig. 2 and similar parts are given similar characters of reference.

It will be noted that the plug 2() carries bayonet pins 21 by which it may be removably inserted within bayonet slots 22 in the rear end of the shell 11. In the structure illust 'ated in Fig. 7 the plug 26, provided with bayonet pins 21, is removably received within the bayonet slots 22 in the rear end of a shell 12 whose :forward end is provided with bayonet slots 31 receiving a lamp similar to the lamps shown in Figs. 1 and 1, similar parts of the lamps having similar characters of reference.

The plug 201 carries a spring barrel 23 that houses a spring 21 which presses a plunger contact 25 forwardly into engagement with the lamp contact 3. The rear end of the spring barrel 23 is formed to constitute a threaded nut 132 that performs the assembling function of the nuts shown in Figs. 2 and 6. The nut 132 is complemental to parts which are similar to the parts complemental to the nuts 13 131 shown in Figs. 2 and 6, all of these complemental parts being given similar characters of reference.

In the form of the invention shown in Figs. 2 and 6 the nuts are provided with screwdriver slots 26 in order that they may be screwed home. In the form of the in-h vention shown in Fig. 9 the spring barrel 23 may be gripped in order to turn the nut 132 home.

In all cases there should preferably be sutlicient clearance between the nuts and the extensions 171 of the sleeve 17 to permit the nuts firmly to press the bights 162 of the wire 16 without having the nuts bottom againstthe sleeve portions 171. By the construction speciied not only is firm electrical engagement effected and maintained between the sleeve 17 and the nut 13 but with.- drawal of the wire 16 from the sleeve 1 7 is positively prevented owing to the presence of the bight 162, the formation4 of this bight being made possible by the provisionv of the external lateral recess 19 in the sleeve 17. rThis `lateral recess is inthe zone of the threads upon the sleeve 17 and in the zone of the threaded portion of the nut that enga the threads upon the sleeves.

IVhile I have herein shown and particularly described the preferred embodiment of my invention I do not wish to be limited to the precise details of construction shown as changes may readily be made without departing from the spirit of my invention, but having thus described my invention I claim as new and desire to secure by Letters Patent the followingz 1. An electrical conductor including. two elements, one in the form of an exteriorly threaded sleeve and the other in the form of a nut upon the threaded sleeve, this nut h aving a wire engaging end Wall; and Wire passing through the bore of the sleeve and having an end portion returned upon the exterior` of the sleeve to form a bight in the wire at one end of the sleeve, there being an external recess upon a lateral portion of the sleeve and in the zone of the threads on the sleeve and in the zone of the threaded portion of the nut that engages the threads upon the sleeve, said recess receiving said end portion of the Wire, said bight being engaged by the aforesaid end Wall of the nut to maintain the bight in the Wire in rm engagement with said sleeve and nut.

2. An electrical conductor including two elements, one in the form of an exteriorly threaded sleeve and the other in the form of a nut upon the threaded sleeve7 this nut having a Wire engaging end Wall; and wire passing through the bore of the sleeve and having an end portion returned upon the exterior' of the sleeve to `form a bight in the wire at one end of the sleeve, there being an external recess upon a lateral portion of the sleeve and in the zone of the threads on the sleeve and in the zone of the threaded portion of the nut that engages the threads upon the sleeve, said recess receiving said end portion of the Wire which is eoniined in said recess by engagement With the inner side of the nut.

In Witness whereof, I hereunto subscribe my name this thirtieth day of January A. D., 1918.

HARRY A. DOUGLAS. 

